Look! Lily with her sister _________ a kite on the playground.
The machine might break down someday in the future, ____, you can dial this number for help.
_________ returns first will win the big prize.
—Mary said Leo worked really hard. — _______.
— I regret _______ you that you failed the exam. — How I regret _______ so much time playing computer games.
The doctor insisted that the patient ______ seriously ill and that an operation _____ in no time.